Chapter 14: Biocorrosion in drinking water distribution systems

Abstract

Due to the morphology of biofilms, which in most cases are present as a heterogeneous, non-continuous deposit or coating, on the metallic surface, microbially-influenced corrosion (MIC) occurs as localized attack in the form of pitting. In water distribution systems, this type of corrosion often leads to extensive perforation of piping material. Although microorganisms detected within biofilms on corroded metallic materials include bacteria, fungi and algae, the majority of research efforts have focused on the role played by bacteria in corrosion processes. The main types of bacteria found on such materials are sulphate reducing bacteria (SRB), sulfur-oxidizing bacteria (SOB), iron-oxidizing/reducing bacteria (IOB/IRB), manganese-oxidizing bacteria (MOB), as well as bacteria secreting organic acids and slime. Biofilm-influenced corrosion within drinking water treatment and distribution system is dependent upon a complex interaction of chemical, physical, operational, and engineering parameters. Hence each of these parameters should be considered while devising a solution to the MIC problem.